[ntp:questions] Befuddled and confused, again...

Rob nomail at example.com
Tue Feb 16 10:22:48 UTC 2010

David Lord <snews at lordynet.org> wrote:
> David Woolley wrote:
>> David Lord wrote:
>>> Systems seem heavily overloaded.
>>> My 3G mobile broadband has seconds of latency whilst initiating
>>> connections, that is how the system works, maybe 10 seconds, but
>> That's likely to be result of the power management design, not of overload.
> No, connection is already established, PPP is already up and
> routing all setup. Possibly ssh connected but no traffic.

He is correct, it is a power- and traffic management issue, not something
unique to the UK.

There are some polling rates in the 3G protocol that adapt to the actual
traffic.  When a connection has been idle for long, it can take some time
to come back when you suddenly use it.  When there is occasional traffic,
it will take around 400ms.  Once there is lots of traffic (more than
a few packets per second), the roundtriptime will drop to 80-100ms and
stay there until there is less traffic.
E.g. pinging it at 1 second intervals will not keep it at the fast rate.
Pinging 5 times per second (ping -i 0.2) will.

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